static void halfSort(final int[] a) {
	  for (int i = 0; i < a.length / 2; i++) {
		var lowestIndex = -1;
		var lowestValue = -1;
		for (int j = i; j < a.length; j++) {
			if(lowestIndex == -1 || a[j] < a[lowestIndex]) {
				lowestIndex = j;
				lowestValue = a[j];
			}
		}
		System.arraycopy(a, i, a, i+1, lowestIndex-i);
		a[i] = lowestValue;
	  }
  }